Alpine plant recruitment processes across altitudinal gradients and the implications with imminent climatic change

Susanna Venn
PhD candidate, Dept Botany, LaTrobe University, Bundoora, VIC 3086

Received the Australian Flora Foundation Young Scientist Award for her talk at ESA2005, the Ecological Society of Australia Conference on the 29th November – 2nd December 2005 at the University of Queensland, St Lucia, Brisbane for her talk

This research aims to investigate the role of alpine plant recruitment processes with regard to environmental gradients and assess how Australian alpine plants may respond to a changed climate in the future. Using mountain peaks of varying elevations as a naturally occurring environmental gradient, I may be able to predict how climate change will influence plant communities in the future by assessing the success of current recruitment processes at different altitudes. Using this gradient of sites and “space-for-time” approach we assume that species will track a changing climate over time in the same way that they vary with climate now in space; therefore we expect the highest peaks to experience typically lower-peak climates in the future. Alpine species will need to continue to recruiting sexually, producing viable seed and establishing robust seedlings which survive into adults if they are to make any necessary range shifts and survive in the long-term. The patterns seen in these processes will be correlated to the patterns in species’ spatial distributions, within and between Victorian mountain tops. Patterns seen in field experiments will be supported by glasshouse and growth-cabinet experiments examining seed viability and germination rates. I will also run field experiments examining soil nitrogen availability across a range of altitudes along with plant-litter decomposition rates and the role of the soil seed bank, and relate these to plant species distribution patterns and species’ long-term survival with the additional effects of a warmer climate.

In summary, the following questions will be addressed:
Which species may be able to tolerate or adapt to rapid climatic change?
Which will become more competitive for resources?
Are species geographic locations restricted by nitrogen availability and uptake?
Will rare and threatened species be at further risk of extinction?